1. Field of the Invention
The present invention relates generally to concrete reinforcement wire and more particularly, to a weld-less, self spacing and self supporting device for reinforcement of concrete.
2. Description of the Related Art
The use of reinforced concrete has revolutionized the construction industry, providing superior structural and load bearing characteristics while minimizing material costs. In laying reinforced concrete roads, a series of steel reinforcing screens are positioned in a continuous, grid-like fashion within the poured concrete area.
In pouring reinforced concrete, it is essential that the grid structure of the reinforcement bars be contiguous throughout each structural element so as to avoid forming weak spots in the structure. In doing so, conventional methods involve connecting adjoining reinforcing bars together either by welding or by overlapping their ends and wrapping them together with wire. In the latter scenario, the wrapping is typically done by hand and, as a result, can become labor intensive and time consuming.
The type of reinforcing screens most widely in use today consists of a pair of parallely spaced heavy gage steel wires, held approximately four inches apart by a series of spaced crosswires made of the same material. Each crosswire is welded at its top and bottom to each parallely spaced heavy gage steel wire, and extends outward slightly above and below. This screen is then stored and deployed in sections.
The strength of this conventionally available screens is independent of the gage of the wire, but is rather only as strong as the welds holding each wire to its crosswires. Also, because of the need to use welding at all, the materials used are limited to common steels, resulting in problems with corrosion.
Due to the tremendous number of linear feet of reinforcing screen as well as the associated supporting high-chair type spacers required for roadwork, until now no device has shown to be able to overcome these problems at a reasonably comparable cost.
Numerous attempts have been made to correct for the foregoing problems. For instance, U.S. Pat. No. 4,080,770, issued in the name of Vigh, discloses a high chair spacer for use in concrete construction and casting. However, a spacer made in accordance with this reference would be impractical, both in terms of material and in terms of installation labor, for use in pouring concrete roads.
Also, U.S. Pat. No. 4,452,026, issued in the name of Tolliver, discloses a spacer for wire reinforcement. Such a device, however, is used in conjunction with conventional wire screens, and serves only to increase the cost and installation difficulty.
And, in U.S. Pat. No. 5,896,722, issued in the name of Swensen, a weldless spacer is disclosed, but is best suited for spacing vertical rebar elements for structures such as walls and columns, not roads.
Finally, in U.S. Pat. No. 5,832,690, issued in the name of Kaines, a spacer for double cage concrete reinforcement wire grids is disclosed, but again is used in conjunction with conventional wire screens, and serves only to increase the cost and installation difficulty.
Consequently, a need has been felt for providing an apparatus and method which overcomes the safety and corrosion concerns of the present art without increasing installation costs or difficulty.
It is therefore an object of the present invention to provide an improved weldless spacer for wire reinforcement of concrete.
It is a feature of the present invention to provide an improved weldless spacer for wire reinforcement of concrete that can be made in a continuous, stamped fashion.
Briefly described according to one embodiment of the present invention, a weldless spacer for wire reinforcement of concrete is provided formed of a one piece, stamped design. Of a linear sectioned of a rectangular piece of metal an upper rail is formed parallel to a lower rail. A series of vertical support elements are notched therebetween, parallel to each other but perpendicular to both the upper rail and the lower rail. A window orifice is formed therebetween, and during the manufacturing process a rectangular cutout blank will be formed. Since it is envisioned that the manufacturing process will entail metal stamping on a continuous basis, although the cutout blank can be scrapped it is envisioned that additional functional elements, though unrelated to the present invention, can be incorporated directly into the die and thereby greatly reduce the amount of unused waste material.
An advantage of the present invention is that a spacer for wire reinforcement of concrete is provided that can supplant entirely the use of conventional reinforcing screen supports.
Another advantage of the present invention is that a spacer for reinforcement of concrete can be provided that is free of welded stress points.
Further, a preferred embodiment of the present invention can be formed of galvanized or other material, but can be deployed and used in a manner similar to current conventional techniques.